The study of diseases in horses encompasses a wide range of conditions affecting equine health, including infectious diseases, metabolic disorders, and genetic abnormalities. These diseases can impact various systems within the horse, such as respiratory, gastrointestinal, and musculoskeletal systems, and can lead to significant health challenges. Research in this area focuses on understanding the pathophysiology, diagnosis, prevention, and treatment of equine diseases. Common diseases studied include equine influenza, equine herpesvirus, and laminitis. This page provides access to peer-reviewed research studies and scholarly articles that explore the etiology, clinical presentation, and management strategies of diseases in horses, contributing to the advancement of equine veterinary medicine.
Powell DG, Dwyer RM, Traub-Dargatz JL, Fulker RH, Whalen JW, Srinivasappa J, Acree WM, Chu HJ.To determine safety, immunogenicity, and efficacy of an inactivated equine rotavirus vaccine. Methods: Prospective randomized controlled trial. Methods: 316 pregnant Thoroughbred mares during the first year of the study and 311 during the second year. Methods: During the first year, mares received 3 doses of vaccine or placebo, IM, at 8, 9, and 10 months of gestation. Serum neutralizing antibody titers were measured before vaccination and 1 and 35 days after foaling. Antibody titers were measured in foals 1, 7, 35, 60, 90, and 120 days after birth. During the second year, mares that had been v...
Ball MA, Rebhun WC, Gaarder JE, Patten V.To evaluate the efficacy of itraconazole-dimethyl sulfoxide ointment for treatment of keratomycosis in horses in the northeastern United States. Methods: Prospective clinical trial. Methods: 9 horses (10 affected eyes). Methods: All horses treated for keratomycosis at Cornell University between July 1994 and July 1996 were included in the study. The diagnosis of keratomycosis was confirmed by cytologic examination, and all horses were treated with 0.25 ml of a 1% itraconazole-30% dimethyl sulfoxide petrolatum-based ointment, applied to the affected eye every 4 hours. Results: Topical applicati...
Baylis M, el Hasnaoui H, Bouayoune H, Touti J, Mellor PS.African horse sickness (AHS) is a vector-borne, infectious disease of equines that is caused by African horse sickness virus (AHSV). The only proven field vector is the biting midge Culicoides imicola, although C. obsoletus and C. pulicaris are suspected vectors. There was a recent epizootic of AHS in Iberia (1987-90) and Morocco (1989-91). In 1994-45 a total of 3887 light trap samples were taken from twenty-two sites distributed over most of Morocco. Culicoides imicola was found to be very widely dispersed, with the greatest catches in the low-lying northwestern areas (between Tangier and Rab...
Yarbrough TB, Carr EA, Snyder JR, Hornof WJ.This article reports an alternative to septal resection in nasal septal deviations involving the rostral 7 to 10 cm of the nasal septum. Methods: Case report. Methods: One client-owned foal. Methods: A nasal approach with mucosal elevation was used to gain access to the cartilaginous portion of the nasal septum. Once exposed, a series of parasagittal incisions in the cartilage allowed the septum to be repositioned while providing some intrinsic stabilization. Results: The nasal approach provided good access to the rostral 7 cm of the nasal septum. The technique resulted in minimal hemorrhage f...
Scrivani PV, Barthez PY, Léveillé R, Schrader SC, Reed SM.Three patients (1 dog, 2 horses) are described where myelography was complicated, purportedly by injection of contrast medium into the meninges superficial to the subarachnoid space. Contrast medium injected in this location in a cadaver tended to accumulate dorsally within the vertebral canal, deep to the dura mater but superficial to the subarachnoid space. The ventral margin of the pooled contrast medium had a wavy or undulating margin and the dorsal margin was smooth. Pooled contrast medium was believed to be sequestered within the structurally weak dural border cell layer between the dura...
Takai S, Takeda K, Nakano Y, Karasawa T, Furugoori J, Sasaki Y, Tsubaki S, Higuchi T, Anzai T, Wada R, Kamada M.To investigate the emergence of rifampin resistance in Rhodococcus equi strains isolated from foals and their environment in Japan, we compared the in vitro antimicrobial susceptibilities to rifampin of 640 isolates from 64 infected foals and 98 soil isolates from their horse-breeding farms. As a control, 39 human isolates from patients with and without AIDS were also tested for susceptibility to rifampin. All of the isolates showed rifampin sensitivity, except isolates from one infected foal and two patients with AIDS that showed rifampin resistance. To investigate the emergence of rifampin-r...
Hultén C, Sletten K, Foyn Bruun C, Marhaug G.Serum amyloid A (SAA) from acute phase horse serum was isolated using hydrophobic interaction chromatography, gel filtration and ion exchange chromatography. Three SAA isoforms with different isoelectric points, i.e. SAA pI 8.0, SAA pI 9.0 and SAA pI 9.7, were identified by two-dimensional electrophoresis and further characterized with amino acid sequence analysis. These isoforms were found in similar concentrations in all animals investigated, with SAA pI 9.7 constituting about half of the total SAA content. Partial amino acid sequence analysis verified the previously published heterogeneous ...
Mills PC, Ng JC, Auer DE.The effect of the acute-phase response (APR) on the activity of the hepatic drug-metabolizing system (DMS) and on the binding of phenylbutazone to plasma proteins was investigated in the horse. An APR was induced by intramuscular injections of Freund's complete adjuvant in five horses and, five days later, these horses together with five clinically normal horses were shot and the right ventral lobe of each liver removed. The hepatic microsomal fractions from the liver samples were isolated and significantly lower (p < 0.01) concentrations of cytochromes P450 and b5 and activities of aniline...
Båverud V, Gustafsson A, Franklin A, Lindholm A, Gunnarsson A.Clostridium (C.) difficile, or its cytoxin, was demonstrated in faecal samples from 10 of 25 (40%) mature horses investigated with acute colitis treated primarily with antibiotics for disorders other than diarrhoea. C. difficile was not found in faecal samples from 140 horses without signs of enteric disorders, from 21 nondiarrhoeic horses treated with antibiotics, nor from 22 horses with colitis untreated with antibiotics. Except for C. difficile neither Salmonella nor any other investigated intestinal pathogen was isolated in any of the diarrhoeic horses. The findings strongly support some e...
Morley PS, Townsend HG.A survey was performed to evaluate the reproductive performance of Thoroughbred mares, estimate risks of dystocia and of morbidity and mortality in foals during the first year post partum and their physical acceptability at age one year. The study population consisted of registered Thoroughbred mares and their foals owned by residents of 4 Western Canadian provinces. Owners were identified using information obtained from the North American Jockey Club, and questionnaires were mailed regarding mares bred in 1988 and their foals born in 1989. Eighty-three per cent of mares were reported to be pr...
Matsuda M, Miyazawa T, Ishida Y, Moore JE.The genomic DNA of eight strains of Taylorella equigenitalis, isolated from seven Norwegian Trotters and a Norwegian pony with contagious equine metritis in Norway, was examined by pulsed-field gel electrophoresis after separate digestions with two restriction enzymes, namely, ApaI and NotI. The respective electrophoretic profiles of the fragments were essentially identical but differed from those of T. equigenitalis NCTC11184T and Kentucky 188. They also exhibited slight differences from profiles obtained from Japanese isolates. These results may possibly suggest a common genotype and a commo...
Theoret CL, Grahn BH, Fretz PB.Atresia of the nasal punctum is the most common congenital anomaly for the equine nasolacrimal system. Nasomaxillary dysplasia has not been previously documented in foals, is of unknown etiology, and appears to be a rare condition. Conjunctivomaxillary sinostomy was successful in resolving the epiphora.
Zheng YH, Sentsui H, Nakaya T, Kono Y, Ikuta K.Equine infectious anemia virus (EIAV) is a good model for studying mechanisms generating escaped retrovirus variants. We previously sequenced the entire gp90-encoding region of 22 cDNA clones obtained from five antigenically distinct isolates (F1V to F5V) recovered during febrile episodes in horse 493 experimentally infected with the Japanese virulent EIAV strain V70. The results showed that the mutations occurred in the principal neutralizing domain (PND) by insertions/duplications. In this study, we further characterized the PND of virus isolates sequentially recovered during 22 febrile epis...
Manohar M, Goetz TE, Sullivan E, Griffin R.The frusemide dose-response for attenuation of exercise-induced pulmonary capillary hypertension was studied in 7 healthy, exercise-conditioned Thoroughbred horses using previously described haemodynamic procedures. Four different doses of frusemide were tested: 250 mg regardless of bodyweight (amounting to 0.56 +/- 0.03 mg/kg bwt), 1.0 mg/kg bwt, 1.5 mg/kg bwt and 2.0 mg/kg bwt. Frusemide was administered i.v., 4 h before exercise. Haemodynamic data were obtained at rest and during treadmill exercise performed at 14.2 m/s on a 3.5% uphill grade; this workload elicited maximal heart rate of ho...
Gustafsson A, Båverud V, Gunnarsson A, Rantzien MH, Lindholm A, Franklin A.In Sweden there are several reports of mares developing acute colitis while their foals were being treated orally for Rhodococcus equi pneumonia with the combination of erythromycin and rifampicin. In this study 6 adult horses were given low oral dosages of these antibiotics, singly or in combination. Within 3 days post administration of erythromycin, in one case in combination with rifampicin, 2 horses developed severe colitis (one fatal). Clostridium difficile was isolated from one of the horses, whereas no specific pathogens were isolated from the other. Both horses had typical changes in b...
Murray MJ, Cavey DM, Feldman BF, Trostle SS, White NA.Sympathetic denervation in a 20-year-old, gray, Thoroughbred-Percheron gelding was manifested by cutaneous hyperthermia and sweating over the right side of the body, demarcated by a line from the withers to the elbow and extending cranially. There was cutaneous hyperthermia over the right side of the head, but other signs of Horner's syndrome (sweating, ptosis, miosis, enophthalmos) were not present. The pattern of cutaneous hyperthermia and sweating was consistent with sympathetic denervation localized to the cervicothoracic ganglion, and thoracic radiographs revealed increased density in the...
Bowles DE, Holden VR, Zhao Y, O'Callaghan DJ.To assess the role of the equine herpesvirus type 1 (EHV-1) ICP0 protein (EICP0) in gene regulation, a variety of molecular studies on the EICP0 gene and gene products of both the attenuated cell culture-adapted Kentucky A (KyA) strain and the Ab4p strain were conducted. These investigations revealed that (i) the ICP0 open reading frame (ORF) of the KyA virus strain is 1,257 bp in size and would encode a protein of 419 amino acids, and in comparison to the ICP0 gene (ORF63) of the Ab4p strain of 1,596 bp (E. A. Telford, M. S. Watson, K. McBride, and A. J. Davison, Virology 189:304-316, 1992), ...
Hosteller DE, Sprecher DJ, Yamini B, Ames NK.Transrectal palpation of an 18-mo-old, anestrous Holstein nulligravida revealed an enlarged left ovary. Ultrasonographically, the mass resembled known equine granulosa cell tumor (GCT) images. Slowly, virilism developed. Fifty-five days after initial diagnosis, unilateral ovariectomy was performed The presurgical serum concentration of testosterone was equal to that of a mature bull. During the 3 mo period following surgery, estrus expression resumed, the serum testosterone concentration returned to baseline, and the heifer was diagnosed pregnant following AI. A low grade, malignant GCT was th...
Hartmann FA, West SE.Phenotypic and molecular techniques, including antimicrobial susceptibility testing, plasmid analysis, and pulsed-field gel electrophoresis (PFGE) were used to characterize 15 isolates of multidrug-resistant (MDR) Salmonella anatum cultured during a 16 mo period from horses and a veterinary clinic environment. The isolates were resistant to multiple antimicrobial agents and could be placed into 4 groups based on their antimicrobial resistance patterns. The isolates contained multiple plasmids ranging in size from 2 to > 100 kb that could be grouped into 3 different plasmid profile patterns;...
Richt JA, Pfeuffer I, Christ M, Frese K, Bechter K, Herzog S.The geographic distribution and host range of Borna disease (BD), a fatal neurologic disease of horses and sheep, are larger than previously thought. The etiologic agent, Borna disease virus (BDV), has been identified as an enveloped nonsegmented negative-strand RNA virus with unique properties of replication. Data indicate a high degree of genetic stability of BDV in its natural host, the horse. Studies in the Lewis rat have shown that BDV replication does not directly influence vital functions; rather, the disease is caused by a virus-induced T-cell mediated immune reaction. Because antibodi...
Khan A, Olajide E, Friedrich M, Holt A, Goehring LS.Equid alphaherpesvirus 1 (EHV-1) is a highly contagious respiratory tract pathogen of horses, and infection may be followed by myeloencephalopathy or abortion. Surveillance and early detection have focused on PCR assays using less tolerated nasal swabs. Here, we assess non-invasive non-contact sampling techniques as surveillance tools in naturally equid gammaherpesvirus 2-shedding horses as surrogates for EHV-1. Horses were individually housed for 10 h periods on 2 consecutive days. Sampling included nasal swabs, nostril wipes, environmental swabs, droplet-catching devices, and air sampling. T...
Atabek B, Zhyldyz A, Aitakin K, Rysbek N, Jailobek O, Ahedor B, Mumbi NNM, Ma Y, Otgonsuren D, Perera WPPSI, Guswanto A, Sivakumar T, Yokoyama N.Equine piroplasmosis is caused by Theileria equi and Babesia caballi, which are hemoprotozoan parasites. Understanding the epidemiology and genotypes of T. equi and B. caballi is crucial for developing effective control strategies in endemic countries. However, the endemic status of these two parasite species remains uncertain in Kyrgyzstan due to lack of surveys. Our study, therefore, aimed to detect T. equi and B. caballi infections in Kyrgyzstan and identify their genotypes. Blood samples were collected from 226 horses across all seven provinces of Kyrgyzstan, namely Chuy, Issyk-Kul, Naryn,...
Gudea AI, Bârcă V, Irimie A, Martonos CO, Socaciu A.The present paper deals with the archaeozoological investigation carried out on a horse skeleton discovered in a Late Iron Age La Tène tomb (coded CX 143) in Alba Iulia, Romania. The paper presents all the results of the investigation, with a description of finds, adding a detailed assessment of the dentition with some interesting conclusions on the usage of a horse bit and the possible consequences of this use. The morphological features of the horse indicate a 7-8-year-old male individual, with a recalculated height of 1200-1300 mm. What is also stressed in the investigated sample is the la...
Heun F, Meißner J, Schieder AK, Ohnesorge B, Busse C.To determine the minimal bactericidal concentration (MBC) and effective contact time of four topical antiseptics-polyhexanide, povidone-iodine (PVP-I), hypochlorous acid (HOCl), and N-acetylcysteine (NAC)-against Pantoea agglomerans, a pathogen frequently isolated in equine ulcerative keratitis. Methods: Over a 17-month sampling period, clinical isolates were collected from horses with ulcerative keratitis. The most frequently isolated strain (Pantoea agglomerans, n = 14) was selected for in vitro analysis. Methods: All isolates were used to determine the MBCs of the four antiseptics. Eac...
Hu Y, Wu G, Jia Q, Zhang B, Sun W, Sa R, Zhang S, Cai W, Jarhen , Ran D, Liu J.Equid alphaherpesvirus 1 (EqAHV1) is a viral pathogen known to cause respiratory disease, neurologic syndromes, and abortion storms in horses. Currently, there are no vaccines that provide complete protection against EqAHV1. Marker vaccines and the differentiation of infected and vaccinated animals (DIVA) strategy are effective for preventing and controlling outbreaks but have not been used for the prevention of EqAHV1 infection. Glycoprotein 2 (gp2), located on the envelope of viruses (EqAHV1), exhibits high antigenicity and functions as a molecular marker for DIVA. In this study, a series of...
Luciani M, Armillotta G, Di Febo T, Krasteva I, Ulisse S, Di Pancrazio C, Laguardia C, Perletta F, Serroni A, Maggetti M, Testa L, Sacchini F....The significance of as the causative agent of dourine cannot be understated, especially given its high mortality rate among equids. International movement of equids should be subject to thorough health checks and screenings to ensure that animals are not infected with . This involves the implementation of quarantine protocols, testing procedures, and the issuance of health certificates to certify the health status of the animals. Three proteins, the peptidyl-prolyl cis-trans isomerase (A0A1G4I8N3), the GrpE protein homolog (A0A1G4I464) and the transport protein particle (TRAPP) component, put...
Marcili A, Sousa IKF, Sousa RDS, Souza RA, Batista GF, Bosco VC, Santos TND, Farias BA, Miranda LM, Soares HS, Onófrio VC, Nieri-Bastos FA. Visceral leishmaniasis is a zoonosis distributed throughout Brazil and caused by the protozoan Leishmania infantum. The disease manifests in its visceral form, with dogs being the primary reservoir. Manaus is the largest city in the Brazilian Amazon region, and despite its significance, there are only documented cases of cutaneous leishmaniasis in humans. The aim of this study was to assess the occurrence of Leishmania infantum in horses in Manaus, Amazonas, Brazil. A total of 178 horses from 16 different properties within the city were sampled, and the specific molecular diagnosis was based...
Peng X, Wang X, Jian J, Zuo Q, Liu H, Wang Y, Su Y, Cao J, Jiang B, Shen Y.Cryptosporidium spp. and Enterocytozoon bieneusi are zoonotic pathogens with global distribution, infecting humans and various livestock. For yaks, Tibetan sheep and horses, the traditional grazing models still hold a main position. After these animals become infected, it not only hinders the development of animal husbandry but also increases the risk of Cryptosporidium spp. and E. bieneusi transmission between livestock and herdsmen. Methods: In the present study, a total of 750 fecal samples were collected from yaks, Tibetan sheep and horses in Shiqu County, Sichuan Province, from July to Au...
Mohammed RR, Tavassoli M, Sidiq KR, Esmaeilnejad B.Neospora caninum ( N. caninum) is the etiologic agent of neosporosis, a potential cause of severe reproductive disorders in cattle, small ruminants, equines, wild animals and canids across the world. The current study is performed to estimate molecular prevalence of N. caninum in small ruminants and equines that had abortion in Kurdistan region of Iraq. A total of 64 tissue samples (brain, placenta, heart, lung and liver) were taken from aborted foetuses, with a total of 122 dam blood samples taken from 63 sheep, 39 goats, 12 mares and 8 jennies in local breed fields. Besides, a risk factor an...
de Klerk J, Tildesley M, Labuschagne K, Gorsich E.Culicoides biting midges exhibit a global spatial distribution and are the main vectors of several viruses of veterinary importance, including bluetongue (BT) and African horse sickness (AHS). Many environmental and anthropological factors contribute to their ability to live in a variety of habitats, which have the potential to change over the years as the climate changes. Therefore, as new habitats emerge, the risk for new introductions of these diseases of interest to occur increases. The aim of this study was to model distributions for two primary vectors for BT and AHS (Culicoides imicola ...
Faghihzadeh Gorji F, Sadr S, Sharifiyazdi H, Borji H.Parasitic infections pose significant threats to humans' and animals' well-being worldwide. Among these parasites, Halicephalobus spp., a genus of nematodes, has gained attention due to its ability to cause severe infections in various animal species, including horses. Objective: This study aimed to determine the prevalence of Halicephalobus spp., specifically focusing on Halicephalobus gingivalis in horses. Methods: In July 2022, a cross-sectional study was conducted in northern Iran to determine the prevalence of Halicephalobus spp. Using standard coprological techniques, 141 fecal samples f...
Kolthammer J.In vitro studies have shown that uncoated carbon and carbon coated with an acrylic hydrogel are capable of adsorbing drugs from horse serum at 37 degrees. Increase in the coating weight from 2 to 4% decreased the rate of adsorption but not the total capacity. In vivo data supports the concept of carbon haemoperfusion for use in the treatment of drug overdose.
Rule EK, Boyle AG, Stefanovski D, Anis E, Linton J, Lorello O.Equine granulocytic anaplasmosis (EGA) is a common disease in adult horses, but clinical disease in foals is rarely reported. The relationship between equine maternal and neonatal antibodies to Anaplasma phagocytophilum is unclear. Objective: That mares in an endemic region would be seropositive for A. phagocytophilum and that mare and foal serum IgG concentrations for A. phagocytophilum would correlate. Additionally, we hypothesized that foal IgG concentrations for A. phagocytophilum acquired by passive immunity would decline by 6 months of age. Methods: Twenty-two healthy mare-foal pairs. ...
de Melo UP, Ferreira C.Oral and dental diseases are common in horses, as evidenced by the results of incidence studies of dental diseases carried out on abattoir specimens or sports horses. Thus, periodic dental examinations in horses are essential to ensure the maintenance of dental health and proper use of ingested food. A retrospective study of the dental records of 416 Quarter Horses (256 males, 160 females), distributed in the western region of the Rio Grande do Norte, Brazil, was conducted. Horses were examined between July 2012 and August 2022. The variables collected were age, sex, type of diet, dental alter...
Ardans AA, Trommershausen-Smith A, Osburn BI, Mayhew IG, Trees C, Park MI, Sawyer M, Stabenfeldt GH.Immunotherapy was attempted in 2 Arabian foals with combined immunodeficiency. One foal was given a transplant of bone marrow from a selected full sibling, and 1 foal was given a fetal thymus transplant. Both foals died. Genetic evidence was obtained for survival of the transplanted tissues in both cases; however, a graft versus host reaction developed in the foal given the fetal thymus transplant.
McIlwraith CW, Owen RA, Basrur PK.Cytogenetic and histological studies were carried out on an intersex horse which was diagnosed clinically as a cryptorchid. Surgery confirmed the horse to be a bilateral abdominal cryptorchid and histological examination revealed ovarian tissue associated with the left epididymis. Chromosome analysis of cultured cells from testicular tissue, ovarian tissue and skin revealed 64-XX and 64-XY make-up, the left gonad containing a greater preponderance of XX cells over XY cells. The external characteristics and behaviour of the horse were indistinguishable from that of a "routine" cryptorchid. Othe...
Dawson FL.Mares rarely ovulate in winter; ovulation is induced by increase in daylight length. Ova accumulate in the oviducts of unserved mares. During pregnancy, corpora lutea accumulate; all regress together at mid pregnancy. Plasma progesterone levels rise and oestrogen levels fall towards the end of pregnancy. Methods are available for early termination of pregnancy and for induction of parturition. Pregnancy can be diagnosed efficiently by rectal examination, and by immunological assay of pregnant mare serum gonadotrophin. Service at the foal heat is associated with an increased prevalence of early...
Levitt NH, Miller HV, Pedersen CE, Eddy GA.The development of a new diagnostic procedure for the identification of Venezvelan, eastern and western equine encephalomyelitis (VEE, EEE, WEE) viruses is described. The procedure utilizes virus precipitation with reference fluorescein-conjugated gamma globulin, followed by cellulose acetate electrophoresis. Clinical specimens containing varying concentrations of virus yielded, in primary duck embryo cell culture, sufficient virus for detection within 22 to 44 hours. Identification of VEE, EEE and WEE virus in specimens was accomplished by microprecipitation within this time. In contrast to c...
Barban PS, Minaeva VM, Pantiukhina AN, Startseva MG.A comparative study was made of the serological properties and virus-neutralizing activity of antiencephalitis gamma-globulin and Fab-fragments isolated from it by gel-filtration. Horse immunoglobulins against the autumno-summer tick-borne encephalitis virus could be disintegrated with the aid of papaine to monovalent Fab-fragments which (according to the complement fixation reaction, the test of suppression of the complement fixation, and the HAIT) retained the serological activity whose level was compared with that of the serological activity of gamma-globulin. Fab-fragments possessed a mark...
Glazier DB, Farrelly BT, O'Connor J.A congenital heart defect characterised by persistent patency (open-ness) of the ventricular septum, permitting flow of blood directly between ventricles, bypassing the pulmonary circulation and resulting in various degrees of cyanosis (blue discolouration of the skin) due to oxygen deficiency. Clinical signs include systolic murmur and a palpable thrill on both sides of the chest, dyspnoea and poor tolerance of exercise.
